The present invention relates to cementing operations and, more particularly, in certain embodiments, to methods and compositions that comprise interground perlite and hydraulic cement.
In general, well treatments include a wide variety of methods that may be performed in oil, gas, geothermal and/or water wells, such as drilling, completion and workover methods. The drilling, completion and workover methods may include, but are not limited to, drilling, fracturing, acidizing, logging, cementing, gravel packing, perforating and conformance methods. Many of these well treatments are designed to enhance and/or facilitate the recovery of desirable fluids from a subterranean well.
In cementing methods, such as well construction and remedial cementing, settable compositions are commonly utilized. As used herein, the term “settable composition” refers to a composition(s) that hydraulically sets or otherwise develops compressive strength. Settable compositions may be used in primary cementing operations whereby pipe strings, such as casing and liners, are cemented in well bores. In performing primary cementing, a settable composition may be pumped into an annulus between a subterranean formation and the pipe string disposed in the subterranean formation. The settable composition should set in the annulus, thereby forming an annular sheath of hardened cement (e.g., a cement sheath) that should support and position the pipe string in the well bore and bond the exterior surface of the pipe string to the walls of the well bore. Settable compositions also may be used in remedial cementing methods, such as the placement of cement plugs, and in squeeze cementing for sealing voids in a pipe string, cement sheath, gravel pack, formation, and the like.
The hydration of the cement in these cementing methods is a complex process because several phases may take part in the reaction simultaneously. In order to control the reaction processes to render the compositions suitable for well cementing, various additives such as retarders, strength enhancers, and accelerators may be added. However, the operating conditions for wells are becoming more challenging and demanding, and the search for new materials continues to meet these challenges. For instance, cement slurries used in well cementing often encounter problems of gaining sufficient strength in a reasonable amount of time for well operations to continue. The costs associated with wait-on-cement (“WOC”) play an important role in well cementing.